U.S. Pat. No. 5,916,113 A describes a corn harvesting attachment that can be attached to a self-propelled harvesting machine, wherein a series of conveying elements with approximately vertical axes of rotation are arranged along both sides of the picking gap. The conveying elements are provided with conveying fingers that are oriented radially with respect to the axis of rotation and convey the plants along the picking gap. With respect to the conveying direction, the conveying elements are arranged, offset relative to one another, on both sides of the picking gap such that the plants are conveyed due to their alternating interaction with the conveying elements on both sides. At the inlet end of the picking gap, a conveying element is provided only on one side, wherein said conveying element is only able to laterally convey the plants into the picking gap a short distance. This means that this conveying element conveys the plants almost exclusively rearward. A conveying element is not provided on the opposite side of the inlet end, so that the plants are introduced into the picking gap only by the stalk dividers and the rounded inlet side of the stripping plate that defines the picking gap. Only a small operating width of the individual gathering and picking units can be achieved in this fashion.
DE 197 34 747 A describes a corn harvesting attachment that cuts plants standing in a field independently of the rows planted and picks the ears off the corn plants. This attachment comprises a cutting mechanism for grasping and cutting the plants independently of the crop rows, wherein the cutting mechanism comprises a rotating drum with recesses on the outer circumference to accommodate the plant stalks and a rotating cutting disk arranged underneath the drum. The plants are conveyed to conventional picking units arranged downstream of the cutting mechanism. The separated ears of the plants are then additionally conveyed by means of two chain conveyors arranged above the picking gap. In one embodiment, two adjacent cutting mechanisms feed the plants to a picking unit arranged between the cutting mechanisms. One disadvantage of this device can be seen in the relatively long structural length caused by the use of the cutting mechanisms and the picking units arranged downstream from them. This also results in a high total weight and a center of gravity of that is relatively forward.
DE 100 28 887 A describes another corn harvesting attachment, in which a gathering element rotates about an approximately vertical axis and is provided with radially oriented carrier elements grasps the stalks of plants standing in a field and conveys the plants along the picking gap of a picking device. Use of a rotating gathering element permits the operating width to be increased in comparison with conventional pickers that operate with gathering chains, since plants that stand laterally adjacent to the picking gap are also drawn in. Because the gathering element also conveys the plants through the picking gap, the structural length is reduced in comparison with the embodiment described in DE 197 34 747 A. In order to prevent possible conveying problems during the introduction of plants into the picking gap, DE 100 28 887 A proposes to arrange another conveying element that introduces the plants into the picking gap and is realized in the form of a screw conveyor or a chain conveyor on the side situated opposite to the gathering element. However, conveying problems can still arise under certain harvesting conditions.